Dual axle unit



2 Sheets-Sheet 1 s. F. BAKER DUAL AXLE UNIT Fi led Nov. 19, 1936 May 3, 193 8.-

mvNoN Q sobmnB z WMJM W5 May 3, 1938. s. F. BAKER 2,116,486

DUAL AXLE UNIT Filed Nov. 19, 1936 2 Sheets-Sheet 2 :7 3 WM *0 Q i SOlzylw/LRBaker Patented May 3, 1938 v v d UNITED STATES PATENT OFFICE:

mesne assignments, to Patent Developers, 1110.,

Detroit, Mich, a corporation of Michigan Application November 19, 1936, Serial No. 111,735

10 Claims. (c1. 180--22) v This invention relates to dualaxle driving units Still another object is to so divide the housing for motor vehicles and more particularly to. the that assembly and disassembly of the idlergear construction and mounting of the transmission shaft as well asthe othervparts of the transcasings in units of this character. mission may bereadily accomplished.

t In a transmission unit of thetype in question A still further object istoprovide an improved 5 wherein a propeller shaft transmits power to the shifter device for. use in connection with the dual driving axles through a train of gears change speed gearing of i a dual axle drive unit mounted on vertically spaced axes it'is necessary of the character to whichthe inventionp'ertains. to employ a relatively large transmission casing These and other objects and advantages of the or housing. Since these housings, as heretofore invention will become more fully apparent here- 10 constructed, are subject to a variety of stresses inafter as reference is had to the accompanying and strains arising both from the transmission drawings wherein one embodiment of the invenof torque and frornthe irregular movements of tion is illustrated by way of example only and in the driving wheels of the vehicle during operation, which: d r v i it has been necessary to make the housing of Fig. 1 is a vertical sectionthrough one form 15 heavy and expensive construction, The principal of dual axle drive unit embodying the invention, objects of the present invention are therefore taken substantially along the line l--'l of Fig. 2 directed to the relief of stresses and strains arisbut with certain parts shown in full and others ing from the. transmission of torque and other broken away in order to more clearly illustrate operating conditions, and to the provision of an t the construction; i so improved transmission and transmission hous Fig. 2 isan end elevation, partiallyin section, ing and novel means for mountingand strengthof the unit shown in Fig. i 1, the section being ening the same. taken substantially along the line 2-2 of Fig. 1; One of the objects. is to provide a cross-brace and, substantially centrally of the transmission cas- Fig. 3 is a horizontal section through the upper 25 ing or housing and to employ this crossbrace as end of the transmission casing taken substana gear supportingmember, thereby ri'gidi fying tially alo the line 0fF1gw2- the housing and at the same time distributing In the 8 e e wh e reference char-- the loading of the central or idler gears over the acters indicate like parts throughout the several housing generally. views, I indicates the frame of a motor vehicle to 30 More specifically, it is proposed to render stawh ch are d, at pos ns tween the dual tionary the lay shaft of the gear train, and to fix driving a les (indicated at 24 F apair this shaft with respect to the walls of the casing of trunnion brackets 2. The trunnion brackets so that it may act as a true b a I thi man- 2 are provided with lower removable bearing caps 5 her it is possible to employ. a substantially lighter 1 which a p d to be S tab y se ured to casing which, at the same time, will be 1 likely the brackets as by bolts and to clamp thereto todistort under the stresses and stralnsprothe outer ends'of a pair of trunnions 3. The duced by the relatively severe operating condiinner ends of trunnions 3 are bolted or otherwise tions encountered by dual axle drive-vehicles. secured to and supp a casing 6 Within which 40 Another object is to provide improved means are housed the elem n s of a r le p d. 40 for mounting the transmission casing of a dual differential pp gear train p d to transaxle drive unit on the frame of a vehicle and for mit driving torque ro t P p r aft '3 preventing undesirable movement of said casing t Vehicle to the o andem d iving axles 24.

relatively to the frame during operation of the The outer ends of trunnicns 3, which extend out- 145. vehicle. d wardly beyond the trunnion brackets 2, serve to A further object is to additionally strengthen support trunnion caps 4 which are pivotally the casing adjacent the propeller shaft gears mounted thereon and to which are secured the while improving the lubricationthereof. In at-- mid-points of the main vehicle springs 5, the taining this object, there are provided ribs inlatter being arranged in pairs with the adjacent teriorly of the top of the casing and a cap for ends of each pair interconnected by suitable 50 the end of the upper gear shaft, this cap being brackets 50, in which arerotatably supported the securely fixed to the casing and forming awell housings of driving axles 24. l whereby lubricant from the top of the casing may As shown best in Fig. 2, the transmission casing follow the ribs in draining through the bearings 6 is divided along a horizontal plane above the and back into the casing proper. axis of trunnions 3 into bottom and top-portions 66.

and on which rotate without driving either gear.

' wall of casing 6 1 cover plate 3i axles 24.

adapted to be bolted together as at I. Hie top portion of the casing has journalled therein in suitable bearings a shaft 8 upon which are rotatably mounted a pair of gears 8 and III of different is splined a shifter clutch the lubricant. In order to assist in accomplishing, this result, bosses are provided which extend substantially into the casing 6 for abutment against the inner races of the bearings 29 for the multiple gear 2'! mounted on fixed lay shaft engaged and operated by a fork l2 and adapted I 28 -either to drivingly connect said shaft to one or the other of said gears or to permit said shaft to In the embodiment illustrated, the shaft 8 is connected by splines at one end to and driven by the vehicle propeller shaft II, the other end of shaft 8 ex tending through the bearing carried by the rear and being .covered by a. cap I 8 which is so arranged as' to form a well into which lubricant is adapted to drain through a suitable .lipped passageway in the bearing supporting plate from the ribs' i8 formed interiorly of the top of the casing 8.,

As illustrated in Fig. 3, the shank of fork l2 extends laterally outwardly through a suitable opening in the casing 8 and is secured to a shifter bar of rod 30 adapted to be operated from the driver's position of the vehicle.- A suitable cover plate 8|, detachably secured to casing 8 as by bolts, slidably supports shifter bar. 80 and covers the opening in the side of the casing through which the fork shank extends, said plate also housing a spring pressed detent 32 adapted to engage any one of three notches formed in bar 38 so as to yieldingly maintain the shifter clutch II in whichever of its three operative positions may be selected by the operator. With this construction, the shifter fork I2, bar 30, detent 32 and may be mounted and demounted as a unit independently of the mechanism within casing 6,

The lower section of the housing 6 rotatably supports in suitable bearingsa difierential gearing arrangement including a driving gear l1, pinions l8 and sun gears 19, the latter being drivingly connected to a pair ofrelatively short shafts 2| through universal joints 28 both sides of which joints are splined to give a full floating relation. The shafts 2| transmit the driving torque from the differential gearing to pinions 22 which engage the gears 23 drivingly connected, as through the The pinions 22, gears 23, axles 24 and the major portions of the shafts 2| reside in banjo housings 25 slidably connected at 33 to torque bells 26 which have swivel fits in the bell housings 34 fixed to the casing 6.-

ple gear 21 is interposed therebetween, one portion of said gear being in permanent mesh with both gear 9 and driving gear I! of the diflerential and the other portion permanently meshing with gear I 8. This multiple gear 2! is rotatably mounted on a stationary lay shaft 28 by means of bearings 28 located at the ends of the gear, the shaft 28 having its axis positioned in the plane of division between the upper and lower portions of the casing 6 and being tightly clamped in place therebetween upon assembly of the casing.

' It will be noted that there is substantial spacing between the end faces of gears 8, l8 and 21. and the walls-of the casing 6. This is a highly desirable featurein that it permits the free return of lubricant to the bottom of the casing, as distinguished from a structure having walls so close to the gears that an upward pumping action interferes with the intended circulation of usual differentials, to the dual' wherein the vehicle In a dual axle drive unit of the construction above described, there is a tendency for the trans-' mission housing 6 to rotate about the axis of trunnions 8 due to torque reaction and other stresses produced during operation of the vehicle particularly when passing over rough ground. The invention therefore includes means for resisting and preventing such undesirable movement of the transmission casing, said means taking the form of a torque tube It surrounding the propeller shaft l3 and secured at its forward and rear ends, respectively, to a fixed cross member 36 of the vehicle frame and the upper portion of the transmission casing 6 adjacent the bearing for the forward end of shaft 8. While the use of a torque tube of this character'efiectively prevents rotational movement of the transmission casing about the trunnion axis, it also gives rise to undesired stresses tending to flex the walls of the casing, particularly when the casing is relatively large as is usual in units of this type,v Distortion or straining of the casing as a result of these stresses is subtantially prevented, however, by fixedly clamping the lay shaft 28 innon-rotatable relation between the upper and lower portions of the casing 6 in such a manner as to materially rigidify the casing walls.

There is thus provided by the present invention will now become apparent to those skilled in the art, may be made in the form, details of con struction and arrangement of the parts shown without departing from the spirit of the invention Reference is therefore to be had to the appended claimsfor a definition of the limits of the invention.

This application is a continuation in part of Serial No. 2,721, filed January 21, 1935.

What is claimed is:

1. In a .dual axle drive for motor vehicles propeller shaft drives said axles through a transmission located between the axles, a gear casing located between said dual driving axles, trunnion members extending -lat erally from the lower portion of said casing and supporting the latter from the vehicle frame, a driving shaft rotatably mounted in the upper portion of said casing and operatively connected with the vehicle'propeller shaft,.means including gearing mounted in said casing for transmitting driving torque from said driving shaft to said axles, and a rigid element secured both to the upper portion of said casing and to a fixed portion of the vehicle frame so as to oppose rotative movement of said casing with respect to the axis of said trunnion members.

2. In a dual axle drive for motor vehicles wherein the vehicle propeller shaft drives said axles through a transmission located between the axles, a gear casing locatedbetween said aria-ice 3 with-the vehicle propellershaft, means including,

gearing mounted in said casingfor transmitting driving torque from said driving shaft to said axles, a rigid element secured both to the upper portion of said casingand to a fixed portionof the vehicle frame so asto oppose rotative move-' ment of said casing with respect to the axis of said trunnion members, and e bracing member rigidly connecting two of the oppositewalls of said casing and reinforcing the same against the stresses set up by opposition of said element to said rotative movement of the, casing, said brac-I ing member lying intermediate the horizontal axial planes of said driving shaft and trunnion members. i h a 3. In a dual axle drive for motor vehicles wherein the vehiclepropeller shaft drives said axles through a transmission located between the axles, a gear casing located between said dual driving axles, trunnion members extending laterally from the'lower portion of said casing and supporting the latter from the vehicle frame, a driving shaft rotatably mounted in the upper portion of said casing and operatively connected with the vehicle propeller shaft, a second shaft mounted in the intermediate portion of said casing between the horizontal axial planes of a said driving shaft and trunnion members, intermeshed gears mounted on said shafts, means mounted in the lower portion of said casing for transmitting driving torque from said gears to the driving of the vehicle frame so as to oppose rotative movement of' said casing with respect to the axis of said trunnion members. a

4. In a dual axle drive for motor vehicles wherein the vehicle propeller shaft drives said axles through a transmission located between the axles, a gear casing located between said dual driving axles, trunnion members extending laterally from the lower portion of said casing and supporting the latter from the vehicle frame, a driving shaft rotatably mounted in the upper portion of said casing and operatively connected with the vehicle propeller shaft, a second shaft mounted in the intermediate portion of said casing between the horizontal axial planes of said driving shaft and trunnion members, intermeshed gears mounted on said shafts, means mounted in the lower portion of said casing for transmitting driving torque from said gears to the driving axles, and a rigid element secured both to the upper portion of said casing and to a fixed portion of the vehicle frame so as to oppose rotative movement of said casing with respect to the axis a to said rotative movement of the casing.

said casing and a fixed portion of said vehicle frame and opposing rotative movement of said casing with respect to the axis of said trunnions, a second gearshaft fixed in said-casing, intermeshed gears mounted on saidshafts, and axle driving gear members mounted in-said casing be- 5 low said secondgear shaft and in driven relation with said intermeshed gears, said second gear shaft being mounted in said casing between the trunnions and said torque tubeand reinforcingsaid casing, to, prevent strains therein as a result of stresses set up by the opposition of saidtorque tube to rotative movement of said casing. 6. In a transmission for the dual driving axlesof a motor vehicle wherein a propeller, shaft drives two axlesthrough a train of gearing lo- 16 cated between said axles, a transmissionfcasing, trunnions supporting said casing from the frame of said vehicle, a rigid element connected both to said casing at a point remote from said trunnions andto a fixed portion of the vehicle frame m tion with the propeller shaft, a lay shaft hava ing, gears rotatable thereon and in mesh with the first named gears, and further gears journalled in said casing in mesh with the gears of said lay shaft, said lay shaft being fixedly secured to opposite walls of said casing to prevent strains therein due to stresses set up by opposition of 80 said rigid element to rotative movement of said casing.

7. In a transmission for the dual driving-axles of a motor vehicle wherein a propeller shaft drives two axlesthrough a train of gearing lo- 'cated between said axles, a transmission housing for the gear train divided horizontally into upper and lower sections, supporting trunnions extending laterally from the lower section of said housing and supporting the latter from the frame 40 ofsaid vehicle, a rigid element connected both to the upper section of said housing and to a fixed portion of the vehicle frame and opposing rotative movement of said housing about the axis of said trunnions, a gear shaft journalled in said upper section and drivably connected with the propeller shaft, a lay shaft rigidly clamped between said housing sections at the juncture thereof, gearing mounted on said gear a and lawshafts and means including additional upper and lower sections, trunnions attached to said lower section and supporting the same from the frame of said vehicle, a gear shaft journalled 50 in said upper section andhaving gearing thereon and a direct driven connection with the propeller shaft, a rigid element connected at one end to said upper section adjacent saidpropeller shaft and at .the other end to a fixedportion 5 of the vehicle frame, a lay shaft fixedly supported by said housing at the juncture of said sections and having gears mounted thereon for rotation with respect thereto and in driven relation to the gearing on said gear shaft, and 70 additional gearing journalled in said lower sec-, tion for actuation from the gears of said lay shaft.

9. In a transmission forthe dual driving axles. of a motor vehicle wherein a propeller shaft drives two axlesthrough a train of gearing located between said. axles, a transmission housing for the gear train divided horizontally into upper and lower-sections, the lower section being supported from the frame of said vehicle by trunnions and theupper section having secured thereto a rigid element also secured to a fixed portion of the vehicle frame and opposing movement, of said housing about the axis of said trunnions, a gear shaft journalled in said upper section and having gearing thereon and a direct driven connection with shaft non-rotatably fixed to said casing between said ,trunnions and rigid element and having idlergears thereon rotatable with respect thereto, vsaid idler gears being integral and having common hearings on said lay shaft, and axle drivinggears rotatably supported in said housing in driven relation to the gears on said lay shaft. 10. In a transmission for the dual driving axles of a motor vehicle wherein a, propeller shaft drives two axles through a train of gearing located between said axles, a transmissionhousing for said gear upper and lower sections, a gear shaft journalled in said upper section and having Bearing theretrain divided horizontally into tional gearing journalled in said casing below the propeller shaft, a lay said lay shaft gears and in engagement therewith, the lower section of said housing having trunnions extending laterally thereof and providing supports therefor, and a torque tube connected to said upper section and to a fixed portion of the vehicle frame and supporting said housing against rotative movement about the axis of said trunnions, said lay shaft being secured to said housing sections whereby it rigidifies the walls thereof to prevent straining thereof in the presence of, external forces tending to cause rotative movement of said housing about the axes of said trunnions.

SOLOMON F. BAKER. 

